000 AXNT20 KNHC 252353 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE AUG 25 2015 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... TROPICAL STORM ERIKA IS CENTERED NEAR 15.8N 53.6W AT 25/0000 UTC OR ABOUT 475 NM E OF ANTIGUA MOVING W 17 KT. ESTIMATED CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. SCATTERED MODERATE/ISOLATED STRONG CONVECTION COVERS THE AREA FROM 13N-16N BETWEEN 51W-53W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 12N-16N BETWEEN 55W-58W. PLEASE SEE THE LATEST FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/ WTNT25 KNHC. ...TROPICAL WAVES... TROPICAL WAVE IN THE W TROPICAL ATLC EXTENDS FROM 23N31W TO A 1011 MB LOW NEAR 15N32W MOVING W-NW 10-15 KT OVER THE PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS EMBEDDED WITHIN A SURGE OF DEEP MOISTURE. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN A 45 NM RADIUS OF 18N31W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS INTO THE E TROPICAL ATLC NEAR 19N16W ALONG 14N27W THROUGH A 1011 MB LOW NEAR 15N32W TO 15N41W. A WEAKENING SQUALL LINE IS GENERATING SCATTERED MODERATE TO ISOLATED STRONG CONVECTION FROM 10N-16N W OF 20W TO INLAND OVER W AFRICA. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER TROUGH EXTENDS ACROSS THE GREAT LAKES AND THE E CONUS TO OVER THE N GULF SUPPORTING A WEAKENING COLD FRONT THAT EXTENDS FROM A 1009 MB LOW IN SOUTH CAROLINA INTO THE GULF BETWEEN CEDAR KEY AND THE BIG BEND AREA ALONG 27N89W TO 29N94W WHERE IT BECOMES STATIONARY TO INLAND OVER GALVESTON TEXAS. SCATTERED TO NUMEROUS SHOWERS/SCATTERED THUNDERSTORMS ARE N OF 27N BETWEEN 92W-96W TO INLAND OVER SW LOUISIANA/SE TEXAS. SCATTERED THUNDERSTORMS ARE ALONG THE REMAINDER OF THE FRONT. AN UPPER LOW IS CENTERED INLAND JUST W OF TAMPICO MEXICO GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 120 NM ALONG THE COAST OF MEXICO BETWEEN TUXPAN AND TAMPICO. AFTERNOON THUNDERSTORMS HAVE DEVELOPED INLAND OVER S FLORIDA...CUBA...AND THE YUCATAN PENINSULA THAT ARE MOVING INTO THE IMMEDIATE GULF WATERS. THE FRONT WILL GRADUALLY DISSIPATE OVER THE N GULF THROUGH WED. CARIBBEAN SEA... A BROAD UPPER LOW IS CENTERED NEAR 15N77W DOMINATING THE CARIBBEAN BASIN AND EXTENDING A TROUGH AXIS ACROSS HISPANIOLA INTO THE CENTRAL ATLC WITH A SECOND TROUGH AXIS EXTENDING SW TO OVER COSTA RICA. A SURFACE TROUGH...REMNANTS OF DANNY...EXTENDS FROM THE SW ATLC NEAR 21N69W ACROSS THE E TIP OF THE DOMINICAN REPUBLIC TO 15N69W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 16N-19N BETWEEN 66W-70W INCLUDING THE PUERTO RICO AND THE E PORTION OF THE DOMINICAN REPUBLIC. AFTERNOON THUNDERSTORMS HAVE DEVELOPED INLAND OVER HISPANIOLA E OF 70W...W CUBA...AND THE YUCATAN PENINSULA. TRADE WIND GENERATED ISOLATED SHOWERS/ THUNDERSTORMS DOT THE CENTRAL CARIBBEAN FROM 12N-17N BETWEEN 75W- 83W. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN UNDER MOSTLY CLEAR SKIES THIS EVENING. THE SURFACE TROUGH...REMNANTS OF DANNY...WILL CONTINUE W ACROSS CUBA THROUGH EARLY FRI. TROPICAL STORM ERIKA WILL MOVE JUST N OF THE LEEWARD ISLANDS THU MORNING. ...HISPANIOLA... ISOLATED AFTERNOON THUNDERSTORMS DOT THE ISLAND W OF 70W WITH SCATTERED SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS COVERING THE DOMINICAN REPUBLIC E OF 70W COMPLIMENTS OF THE SURFACE TROUGH THE EXTENDS ACROSS THE FAR E TIP OF THE ISLAND. THIS SURFACE WILL MOVE W ACROSS THE ISLAND THROUGH WED WITH WIDE SPREAD SHOWERS AND POSSIBLE THUNDERSTORMS SPREADING FROM E TO W. ATLANTIC OCEAN... AN ELONGATED NW/SE UPPER RIDGE IS ANCHORED IN THE W ATLC NEAR 29N70W WITH A RIDGE AXIS EXTENDING SW TO THE STRAITS OF FLORIDA. A REMNANT SURFACE TROUGH IS OVER THE FAR W ATLC FROM 31N78W TO TO OVER FLORIDA NEAR MELBOURNE. A SECOND SURFACE TROUGH IS TO THE E EXTENDING FROM 24N79W ALONG 27N76W 29N71W TO 32N69W WITH SCATTERED TO NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS N OF 28N BETWEEN 65W-74W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 75 NM EITHER SIDE OF THE REMAINDER OF THE SURFACE TROUGH. MOST OF THE ATLC BASIN IS DOMINATED BY A SURFACE RIDGE THAT IS ANCHORED BY A 1022 MB HIGH NEAR 32N37W WITH A SURFACE RIDGE AXIS EXTENDING ALONG 28N52W TO 26N71W. THE W ATLC SURFACE TROUGH WILL DISSIPATE WED AS CENTRAL ATLC THE SURFACE RIDGE SHIFTS WESTWARD. TROPICAL STORM ERIKA WILL MOVE JUST N OF THE LEEWARD ISLANDS BY THU MORNING. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW